Hi Arctos,
As a fledgling woodworker, I used biscuits in constructing my first pair of speakers, Fostex FE267E drivers in bass reflex cabinets, and found them incredibly useful. Putting aside the additional strength they give to the joints, biscuitry allows me to line up the parts precisely.
It's very easy to do. Align the pieces precisely as you want them ultimately to go together, mark them and cut them. I then do a dry run, with biscuits inserted but without glue, to make sure that everything is OK. Then glue up and clamp. If the marks are aligned when I clamp up, I know the pieces are aligned perfectly.
When I took a "woodworking 101" course last fall, the instructor related that some woodworkers contended that biscuit joinery provided little if any additional strength to the joint. He related that tests reported in one of the woodworking mags had disproved this-- in some tests biscuits provided more strength than any other method. He attributed negative attitudes to biscuitry to the fact that it was simply too easy. It was the "easy" part that caught my ear. At all events, speakers are generally not going to be subject to physical stresses (does anyone sit on their speakers?). As it turns out, even if the joint provided no additional strength, I would use it anyway.
